402 NEW YORK STATE MUSEUM 



PLATE 7 



Genus paraptyx gen. no v. 



Page 261 



Paraptyx Ontario sp. nov. 



Page 262 



i A left valve 



2 Umbonal portion of left valve showing striated crescent. X2 



3 A left valve 



4 A right valve 



5 Enlargement of a part of the right valve showing character of 



crescent. X3 

 6, 7 Views of a barite replacement showing the character of the 

 crescent 



8 A left valve 



9 A left valve indicating the notable similarity in form and plica- 



tion to the following species from which it differs in cardi- 

 nal structure, xi.5 

 Naples subprovince Naples 



Genus oNTAHiA gen. nov. 



Page 279 



Ontaria clarkei Beushausen (sp.) 



Page 288 



10 A right valve. X2 



1 1 Cardinal portion of a right valve. X2 



12, 13 Right valves. X2 



14 A small left valve. X2 



i 5 A small right valve 



16 Two small right valves 



1 7 A large right valve 



1 8 A right valve. x2 



19, 20 Cardinal views of specimens having the valves conjoined 



Naples subprovince Naples and vicinity 



